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The Dead Sea Transform (DST) is a prominent shear zone in the Middle East. It separates the Arabian plate from the Sinai microplate and stretches from the Red Sea rift in the south via the Dead Sea to the Taurus-Zagros collision zone in the north. Formed in the Miocene about 17 Ma ago and related to the breakup of the Afro-Arabian continent, the DST accommodates the left-lateral movement between the two plates. The study area is located in the Arava Valley between the Dead Sea and the Red Sea, centered across the Arava Fault (AF), which constitutes the major branch of the transform in this region. A set of seismic experiments comprising controlled sources, linear profiles across the fault, and specifically designed receiver arrays reveals the subsurface structure in the vicinity of the AF and of the fault zone itself down to about 3-4 km depth. A tomographically determined seismic P velocity model shows a pronounced velocity contrast near the fault with lower velocities on the western side than east of it. Additionally, S waves from local earthquakes provide an average P-to-S velocity ratio in the study area, and there are indications for a variations across the fault. High-resolution tomographic velocity sections and seismic reflection profiles confirm the surface trace of the AF, and observed features correlate well with fault-related geological observations. Coincident electrical resistivity sections from magnetotelluric measurements across the AF show a conductive layer west of the fault, resistive regions east of it, and a marked contrast near the trace of the AF, which seems to act as an impermeable barrier for fluid flow. The correlation of seismic velocities and electrical resistivities lead to a characterisation of subsurface lithologies from their physical properties. Whereas the western side of the fault is characterised by a layered structure, the eastern side is rather uniform. The vertical boundary between the western and the eastern units seems to be offset to the east of the AF surface trace. A modelling of fault-zone reflected waves indicates that the boundary between low and high velocities is possibly rather sharp but exhibits a rough surface on the length scale a few hundreds of metres. This gives rise to scattering of seismic waves at this boundary. The imaging (migration) method used is based on array beamforming and coherency analysis of P-to-P scattered seismic phases. Careful assessment of the resolution ensures reliable imaging results. The western low velocities correspond to the young sedimentary fill in the Arava Valley, and the high velocities in the east reflect mainly Precambrian igneous rocks. A 7 km long subvertical scattering zone reflector is offset about 1 km east of the AF surface trace and can be imaged from 1 km to about 4 km depth. The reflector marks the boundary between two lithological blocks juxtaposed most probably by displacement along the DST. This interpretation as a lithological boundary is supported by the combined seismic and magnetotelluric analysis. The boundary may be a strand of the AF, which is offset from the current, recently active surface trace. The total slip of the DST may be distributed spatially and in time over these two strands and possibly other faults in the area.
How to understand species' niches and range dynamics: a demographic research agenda for biogeography
(2012)
Range dynamics causes mismatches between a species geographical distribution and the set of suitable environments in which population growth is positive (the Hutchinsonian niche). This is because sourcesink population dynamics cause species to occupy unsuitable environments, and because environmental change creates non-equilibrium situations in which species may be absent from suitable environments (due to migration limitation) or present in unsuitable environments that were previously suitable (due to time-delayed extinction). Because correlative species distribution models do not account for these processes, they are likely to produce biased niche estimates and biased forecasts of future range dynamics. Recently developed dynamic range models (DRMs) overcome this problem: they statistically estimate both range dynamics and the underlying environmental response of demographic rates from species distribution data. This process-based statistical approach qualitatively advances biogeographical analyses. Yet, the application of DRMs to a broad range of species and study systems requires substantial research efforts in statistical modelling, empirical data collection and ecological theory. Here we review current and potential contributions of these fields to a demographic understanding of niches and range dynamics. Our review serves to formulate a demographic research agenda that entails: (1) advances in incorporating process-based models of demographic responses and range dynamics into a statistical framework, (2) systematic collection of data on temporal changes in distribution and abundance and on the response of demographic rates to environmental variation, and (3) improved theoretical understanding of the scaling of demographic rates and the dynamics of spatially coupled populations. This demographic research agenda is challenging but necessary for improved comprehension and quantification of niches and range dynamics. It also forms the basis for understanding how niches and range dynamics are shaped by evolutionary dynamics and biotic interactions. Ultimately, the demographic research agenda should lead to deeper integration of biogeography with empirical and theoretical ecology.
There Is No Return To Egypt
(2013)
Who are those Polish Jews, who in the wake of the Antizionist Campaign of the year 1968 left their home country and migrated to Israel? How do they, 40 years after these traumatic events, look back at their own history? Which development have they made in the Jewish State, a society torn by wars and inner political tensions? How do they live in Israel at the beginning of the 21st century? In the documentary There Is No Return To Egypt seven members of the Polish-Jewish migration cohort of the late 1960s, early 1970s and there todays environment are represented. These people, while being on camera in their mid-fifties till late seventies of age, allow an intimate view into their Israeli-Polish daily-life and into their world of memories. Interestingly, having survived the atrocities of the Shoah and being forced out of Poland some twenty years later, the older interviewees draw their very own conclusions for their further lives in Israel. In contrast, the younger interviewees deal very differently with the loss of their home and the break in their career life caused by the Antizionist Campaign. The personalities presented in this documentary have various professions: There is a successful musician, a former employee at the Israeli broadcasting service, and there are skilled workers. Their religious identities widely vary: from Jewish orthodox and national-religious to atheist to Judeo-Christian. The protagonists in There Is No Return To Egypt do also represent the political spectrum of Israel: from members of the chauvinist-militarist camp through to members of the peace movement. At the same time, the shooting locations in the documentary are important stages of life for the seven 1968ers: the home being decorated for Shabbat or for Israels national holiday Yom ha-atzmaut, the working place, an army museum, a Jewish settlement in the Palestinian Westbank, a Shoah memorial event at the university campus, a pop concert and a peace demonstration.
Historical narratives play an important role in constructing contemporary notions of citizenship. They are sites on which ideas of the nation are not only reaffirmed but also contested and reframed. In contemporary Germany, dominant narratives of the country's modern history habitually focus on the legacy of the Third Reich and tend to marginalize the country's rich and highly complex histories of immigration. The article addresses this commemorative void in relation to Berlin's urban landscape. It explores how the city's multilayered architecture provides locations for the articulation of marginal memoriesand hence sites of urban citizenshipthat are often denied to immigrant communities on a national scale. Through a detailed examination of a small celebration in 1965 that marked the anniversary of the founding of the modern Turkish republic, the article engages with the layers of history that coalesce around such sites in Berlin.
This reference paper describes the sampling and contents of the IZA Evaluation Dataset Survey and outlines its vast potential for research in labor economics. The data have been part of a unique IZA project to connect administrative data from the German Federal Employment Agency with innovative survey data to study the out-mobility of individuals to work. This study makes the survey available to the research community as a Scientific Use File by explaining the development, structure, and access to the data. Furthermore, it also summarizes previous findings with the survey data.
Background: Five different G protein-coupled sphingosine-1-phosphate (S1P) receptors (S1P1-S1P5) regulate a variety of physiologic and pathophysiologic processes, including lymphocyte circulation, multiple sclerosis (MS), and cancer. Although B-lymphocyte circulation plays an important role in these processes and is essential for normal immune responses, little is known about S1P receptors in human B cells.
Objective: To explore their function and signaling, we studied B-cell lines and primary B cells from control subjects, patients with leukemia, patients with S1P receptor inhibitor-treated MS, and patients with primary immunodeficiencies.
Methods: S1P receptor expression was analyzed by using multicolor immunofluorescence microscopy and quantitative PCR. Transwell assays were used to study cell migration. S1P receptor internalization was visualized by means of time-lapse imaging with fluorescent S1P receptor fusion proteins expressed by using lentiviral gene transfer. B-lymphocyte subsets were characterized by means of flow cytometry and immunofluorescence microscopy.
Results: Showing that different B-cell populations express different combinations of S1P receptors, we found that S1P1 promotes migration, whereas S1P4 modulates and S1P2 inhibits S1P1 signals. Expression of CD69 in activated B lymphocytes and B cells from patients with chronic lymphocytic leukemia inhibited S1P-induced migration. Studying B-cell lines, normal B lymphocytes, and B cells from patients with primary immunodeficiencies, we identified Bruton tyrosine kinase, beta-arrestin 2, LPS-responsive beige-like anchor protein, dedicator of cytokinesis 8, and Wiskott-Aldrich syndrome protein as critical signaling components downstream of S1P1.
Conclusion: Thus S1P receptor signaling regulates human B-cell circulation and might be a factor contributing to the pathology of MS, chronic lymphocytic leukemia, and primary immunodeficiencies.
MULTILIT
(2015)
This paper presents an overview of the linguistic analyses developed in the MULTILIT project and the processing of the oral and written texts collected. The project investigates the language abilities of multilingual children and adolescents, in particular, those who have Turkish and/or Kurdish as a mother tongue. A further aim of the project is to examine from a psycholinguistic and sociolinguistic perspective the extent to which competence in academic registers is achieved on the basis of the languages spoken by the children, including the language(s) spoken at the home, the language of the country of residence and the first foreign language. To be able to examine these questions using corpus linguistic parameters, we created categories of analysis in MULTILIT.
The data collection comprises texts from bilingual and monolingual children and adolescents in Germany in their first language Turkish, their second language German und their foreign language English. Pupils aged between nine and twenty years of age produced monologue oral and written texts in the two genres of narrative and discursive. On the basis of these samples, we examine linguistic features such as lexical expression (lexical density, lexical diversity), syntactic complexity (syntactic and discursive packaging) as well as phonology in the oral texts and orthography in the written texts, with the aim of investigating the pupils’ growing mastery of these features in academic and informal registers.
To this end the raw data have been transcribed by the use of transcription conventions developed especially for the needs of the MULTILIT data. They are based on the commonly used HIAT and GAT transcription conventions and supplemented with conventions that provide additional information such as features at the graphic level.
The categories of analysis comprise a large number of linguistic categories such as word classes, syntax, noun phrase complexity, complex verbal morphology, direct speech and text structures. We also annotate errors and norm deviations at a wide range of levels (orthographic, morphological, lexical, syntactic and textual). In view of the different language systems, these criteria are considered separately for all languages investigated in the project.
Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0% in delta N-15, i.e. two trophic levels, and 4.2% in delta C-13 with a community mean of 11.3% in delta N-15 and - 21.0% in delta C-13. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (delta N-15: 2.4%, delta C-13: 1.0%) with a community mean of 8.0% delta N-15 and - 21.7% in delta C-13. Multivariate analyses and residual permutation of Euclidian distances in delta C-13- delta N-15 bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa.
Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0% in delta N-15, i.e. two trophic levels, and 4.2% in delta C-13 with a community mean of 11.3% in delta N-15 and - 21.0% in delta C-13. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (delta N-15: 2.4%, delta C-13: 1.0%) with a community mean of 8.0% delta N-15 and - 21.7% in delta C-13. Multivariate analyses and residual permutation of Euclidian distances in delta C-13- delta N-15 bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa.
The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding, ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting those of the Central Zagros were somewhat isolated from other populations of the Fertile Crescent. Runs of homozygosity are of a similar length to those from Neolithic farmers, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.
1. Migration conveys an immense challenge, especially for juvenile birds coping with enduring and risky journeys shortly after fledging. Accordingly, juveniles exhibit considerably lower survival rates compared to adults, particularly during migration. Juvenile white storks (Ciconia ciconia), which are known to rely on adults during their first fall migration presumably for navigational purposes, also display much lower annual survival than adults.
2. Using detailed GPS and body acceleration data, we examined the patterns and potential causes of age-related differences in fall migration properties of white storks by comparing first-year juveniles and adults. We compared juvenile and adult parameters of movement, behaviour and energy expenditure (estimated from overall dynamic body acceleration) and placed this in the context of the juveniles’ lower survival rate.
3. Juveniles used flapping flight vs. soaring flight 23% more than adults and were estimated to expend 14% more energy during flight. Juveniles did not compensate for their higher flight costs by increased refuelling or resting during migration. When juveniles and adults migrated together in the same flock, the juvenile flew mostly behind the adult and was left behind when they separated. Juveniles showed greater improvement in flight efficiency throughout migration compared to adults which appears crucial because juveniles exhibiting higher flight costs suffered increased mortality.
4. Our findings demonstrate the conflict between the juveniles’ inferior flight skills and their urge to keep up with mixed adult–juvenile flocks. We suggest that increased flight costs are an important proximate cause of juvenile mortality in white storks and likely in other soaring migrants and that natural selection is operating on juvenile variation in flight efficiency.
Controlling mesenchymal stem cells (MSCs) behavior is necessary to fully exploit their therapeutic potential. Various approaches are employed to effectively influence the migration capacity of MSCs. Here, topographic microstructures with different microscale roughness were created on polystyrene (PS) culture vessel surfaces as a feasible physical preconditioning strategy to modulate MSC migration. By analyzing trajectories of cells migrating after reseeding, we demonstrated that the mobilization velocity of human adipose derived mesenchymal stem cells (hADSCs) could be promoted by and persisted after brief preconditioning with the appropriate microtopography. Moreover, the elevated activation levels of focal adhesion kinase (FAK) and mitogen-activated protein kinase (MAPK) in hADSCs were also observed during and after the preconditioning process. These findings underline the potential enhancement of in vivo therapeutic efficacy in regenerative medicine via transplantation of topographic microstructure preconditioned stem cells.
It is unclear whether Indo-European languages in Europe spread from the Pontic steppes in the late Neolithic, or from Anatolia in the Early Neolithic. Under the former hypothesis, people of the Globular Amphorae culture (GAC) would be descended from Eastern ancestors, likely representing the Yamnaya culture. However, nuclear (six individuals typed for 597 573 SNPs) and mitochondrial (11 complete sequences) DNA from the GAC appear closer to those of earlier Neolithic groups than to the DNA of all other populations related to the Pontic steppe migration. Explicit comparisons of alternative demographic models via approximate Bayesian computation confirmed this pattern. These results are not in contrast to Late Neolithic gene flow from the Pontic steppes into Central Europe. However, they add nuance to this model, showing that the eastern affinities of the GAC in the archaeological record reflect cultural influences from other groups from the East, rather than the movement of people.
Fat loads were quantified for 2125 Yellow-browed Warblers Phylloscopus inornatus trapped at a stop-over site in Far East Russia during autumn migration. Flight ranges of 660–820 km were estimated for the fattest individuals, suggesting that they would need to stop for refuelling at least six times to reach their wintering areas in South East Asia.
Modeling random crawling, membrane deformation and intracellular polarity of motile amoeboid cells
(2018)
Amoeboid movement is one of the most widespread forms of cell motility that plays a key role in numerous biological contexts. While many aspects of this process are well investigated, the large cell-to-cell variability in the motile characteristics of an otherwise uniform population remains an open question that was largely ignored by previous models. In this article, we present a mathematical model of amoeboid motility that combines noisy bistable kinetics with a dynamic phase field for the cell shape. To capture cell-to-cell variability, we introduce a single parameter for tuning the balance between polarity formation and intracellular noise. We compare numerical simulations of our model to experiments with the social amoeba Dictyostelium discoideum. Despite the simple structure of our model, we found close agreement with the experimental results for the center-of-mass motion as well as for the evolution of the cell shape and the overall intracellular patterns. We thus conjecture that the building blocks of our model capture essential features of amoeboid motility and may serve as a starting point for more detailed descriptions of cell motion in chemical gradients and confined environments.
BACKGROUND: The formation of a functionally-confluent endothelial cell (EC) monolayer affords proliferation of EC, which only happens in case of appropriate migratory activity. AIM OF THE STUDY: The migratory pathway of human umbilical endothelial cells (HUVEC) was investigated on different polymeric substrates. MATERIAL AND METHODS: Surface characterization of the polymers was performed by contact angle measurements and atomic force microscopy under wet conditions. 30,000 HUVEC per well were seeded on polytetrafluoroethylene (PTFE) (theta(adv) = 119 degrees +/- 2 degrees), on low-attachment plate LAP (theta(adv) = 28 degrees +/- 2 degrees) and on polystyrene based tissue culture plates (TCP, theta(adv) = 22 degrees +/- 1 degrees). HUVEC tracks (trajectories) were recorded by time lapse microscopy and the euclidean distance (straight line between starting and end point), the total distance and the velocities of HUVEC not leaving the vision field were determined. RESULTS: On PTFE, 42 HUVEC were in the vision field directly after seeding. The mean length of single migration steps (SML) was 6.1 +/- 5.2 mu m, the mean velocity (MV) 0.40 +/- 0.3 mu m.min(-1) and the complete length of the trajectory (LT) was 710 +/- 440 mu m. On TCP 82 HUVEC were in the vision field subsequent to seeding. The LT was 840 +/- 550 mu m, the SML 6.1 +/- 5.2 mu m and the MV 0.44 +/- 0.3 mu m.min(-1). The trajectories on LAP differed significantly in respect to SML (2.4 +/- 3.9 mu m, p <0.05), the MV (0.16 +/- 0.3 mu m.min(-1), p <0.05) and the LT (410 +/- 300 mu m, p <0.05), compared to PTFE and TCP. Solely on TCP a nearly confluent EC monolayer developed after three days. While on TCP diffuse signals of vinculin were found over the whole basal cell surface organizing the binding of the cells by focal adhesions, on PTFE vinculin was merely arranged at the cell rims, and on the hydrophilic material (LAP) no focal adhesions were found. CONCLUSION: The study revealed that the wettability of polymers affected not only the initial adherence but also the migration of EC, which is of importance for the proliferation and ultimately the endothelialization of polymer-based biomaterials.
Historical narratives play an important role in constructing contemporary notions of citizenship. They are sites on which ideas of the nation are not only reaffirmed but also contested and reframed. In contemporary Germany, dominant narratives of the country’s modern history habitually focus on the legacy of the Third Reich and tend to marginalize the country’s rich and highly complex histories of immigration. The article addresses this commemorative void in relation to Berlin’s urban landscape. It explores how the city’s multilayered architecture provides locations for the articulation of marginal memories—and hence sites of urban citizenship—that are often denied to immigrant communities on a national scale. Through a detailed examination of a small celebration in 1965 that marked the anniversary of the founding of the modern Turkish republic, the article engages with the layers of history that coalesce around such sites in Berlin.
Es gibt in Berlin eine einzigartige Vereinslandschaft im Amateur – und semiprofessionellen Fußballsport, in der einst von türkischen Migranten gegründete Vereine einen festen Platz einnehmen. Fußballsport bietet einen sozialen Raum für Jugendliche verschiedener kultureller, ethnischer und religiöser Herkunft, in dem Gruppen gebildet werden, um gegen einander zu konkurrieren. Ebenso eröffnet Fußball dem Einzelnen die Möglichkeit, die Gültigkeit und Relevanz von Vorurteilen und von gängigen Stereotypisierungen anderer Gruppen im Spielalltag einer ständigen Prüfung zu unterziehen. Fußballspieler können sich sowohl zwischen multi-kulturellen als auch mono-ethnischen Gruppenkonstellationen, in einigen Fällen auch in transnationalen Konstellationen bewegen, womit sie dabei wesentlich an der Sinngebung ihrer eigenen sozialen Zugehörigkeit mitwirken, die sich aus dem Spannungsfeld von Selbst- und Fremdwahrnehmungsmustern ergibt. In Folge dessen werden in diesem Raum Anerkennungsmechanismen konstituiert.
Die vorliegende Dissertation befasst sich mit dem alltäglichen Leben von türkisch-stämmigen, jugendlichen Amateur- und semiprofessionellen Fußballspielern (delikanli), sowie von anderen sozialen Akteuren der türkischen Fußballwelt, wie zum Beispiel „ältere“ Fußballspieler (agbi) und Fußballtrainer (hoca). Hauptanliegen der Arbeit war die Rekonstruktion kollektiver Wahrnehmungs-, Deutungs - und Handlungsmuster von Mitgliedern türkischer Fußballvereine im allgemeinen und ihrer Selbstdarstellung aber auch ihrer Wahrnehmung der „Anderen“ im besonderen. Mittels dieser Studie sollte nachvollzogen werden, ob und inwiefern sich traditionelle soziale Verhaltensmuster der gewählten Gruppe im technisch regulierten und stark Konkurrenz-orientierten Handlungsraum widerspiegeln und die reziproken Beziehungen zwischen dem „Selbst“ und den „Anderen“ regulieren. Dabei wurde die Relevanz von herkunftsbezogenen Stereotypisierungen und Vorurteilen in der kollektiven Konstitution von Selbstwahrnehmungen und Fremdverstehen im partikularen sozialen Feld (Bourdieu, 2001) des Fußballs rekonstruiert.
In dieser Arbeit wurde darüber hinaus beleuchtet, welche Rolle türkische Fußballvereine auf der einen Seite bei der Entstehung sozialer Raumzugehörigkeit zu den Stadtquartieren in Berlin einnehmen und welche Art von Mechanismen der sozialen Integration sie in diesen Vereinen herstellen. Auf der anderen Seite wurde hinterfragt, inwiefern sie zur sozialen Kohäsion zwischen diversen Kulturen beitragen. Daher wurde geprüft, ob und inwiefern die negativ konnotierte ethnozentrische Wahrnehmung von „Differenz“ (Bielefeld, 1998), die als soziales Konstrukt zwischen autochthonen und allochthonen Gruppen hergestellt wird, durch das Engagement der Vereinsakteure einen konstruktiven Wandel erfährt.
Übergeordnetes Ziel all dieser Forschungsfragen war es, ein fundiertes Verständnis über die Rolle von türkischen Fußballvereinen als soziale Mechanismen zu erlangen und deren Funktionsweise bei der Konstitution von Anpassungsstrategien in diesem sozialen Feld untersuchen. Detailliert wurde diese Rolle unter der Konzeptualisierung von sozialen Positionierungsmuster betrachtet, die als Gefüge von Deutungen des Alltäglichen verstanden werden, das individuelle und kollektive Handlungsmuster und implizit Muster des Fremdverstehens sowie des othering im Migrationskontext reguliert. Eine Rekonstruktion der sozialen Positionierungsmuster bietet eine eingehende soziologische Untersuchung dieser Teilnehmergruppe, die zudem Aufschluss über die Bedeutung und das Verständnis von ethnischer Zugehörigkeit für letztere gibt.
Neben umfangreicher Feldbeobachtung wurden in dieser qualitativen Studie mit Spielern verschiedener Vereine insgesamt zehn Gruppendiskussionen (Bohnsack, 2004) innerhalb ihrer Mannschaften zu gemeinsamen alltäglichen Erlebnissen und Erfahrungen durchgeführt, aufgezeichnet und mittels sozialwissenschaftlichem hermeneutischem Verfahren (Soeffner, 2004) interpretiert. Auch mit anderen Vereinsmitgliedern, d. h. mit Trainern bzw. hoca, Vorsitzenden, Managern und Sponsoren wurden jeweils zehn narrative und sieben biographische Einzelinterviews sowie sieben Experteninterviews durchgeführt. Deren Analyse erlaubt es, die Rolle dieser Mitglieder sowie wirkende Autoritätsmechanismen und kollektiv konstituierte Verhaltensmuster innerhalb der gesamten Vereinsgruppe zu rekonstruieren. Dabei wurde bezweckt, die Gesamtheit des sozialen Netzwerkes bzw. die Beziehungsschemata innerhalb der türkischen Fußballvereine Berlins zu verdeutlichen.
In der Arbeit werden zwei Standpunkte der theoretischen Auseinandersetzung verwendet. Auf der einen Seite wird die Lebensweltanalyse (Schütz und Luckmann, 1979, 1990) angewendet, um das soziale Erbe der in der Vergangenheit gesellschaftlich konstituierten Titulierung „Menschen mit Migrationshintergrund“ zu rekonstruieren, bzw. den Einfluss dieser sozialen Reproduktion auf die Wahrnehmungs-, Deutungs- und Handlungsmuster der Akteure zu untersuchen. Auf der anderen Seite wird die soziale Wirkung der tatsächlichen, alltäglichen Erfahrungsschemata im sozialen Feld des Fußballs auf die Selbstpositionierungen der Akteure mittels Goffmanscher Rahmenanalyse (Goffman, 1980) herausgearbeitet.
Environmental factors shape the spatial distribution and dynamics of populations. Understanding how these factors interact with movement behavior is critical for efficient conservation, in particular for migratory species. Adult female green sea turtles, Chelonia mydas, migrate between foraging and nesting sites that are generally separated by thousands of kilometers. As an emblematic endangered species, green turtles have been intensively studied, with a focus on nesting, migration, and foraging. Nevertheless, few attempts integrated these behaviors and their trade‐offs by considering the spatial configurations of foraging and nesting grounds as well as environmental heterogeneity like oceanic currents and food distribution. We developed an individual‐based model to investigate the impact of local environmental conditions on emerging migratory corridors and reproductive output and to thereby identify conservation priority sites. The model integrates movement, nesting, and foraging behavior. Despite being largely conceptual, the model captured realistic movement patterns which confirm field studies. The spatial distribution of migratory corridors and foraging hot spots was mostly constrained by features of the regional landscape, such as nesting site locations, distribution of feeding patches, and oceanic currents. These constraints also explained the mixing patterns in regional forager communities. By implementing alternative decision strategies of the turtles, we found that foraging site fidelity and nesting investment, two characteristics of green turtles' biology, are favorable strategies under unpredictable environmental conditions affecting their habitats. Based on our results, we propose specific guidelines for the regional conservation of green turtles as well as future research suggestions advancing spatial ecology of sea turtles. Being implemented in an easy to learn open‐source software, our model can coevolve with the collection and analysis of new data on energy budget and movement into a generic tool for sea turtle research and conservation. Our modeling approach could also be useful for supporting the conservation of other migratory marine animals.
In this paper, we move from the large strand of research that looks at evidence of climate migration to the questions: who are the climate migrants? and where do they go? These questions are crucial to design policies that mitigate welfare losses of migration choices due to climate change. We study the direct and heterogeneous associations between weather extremes and migration in rural India. We combine ERAS reanalysis data with the India Human Development Survey household panel and conduct regression analyses by applying linear probability and multinomial logit models. This enables us to establish a causal relationship between temperature and precipitation anomalies and overall migration as well as migration by destination. We show that adverse weather shocks decrease rural-rural and international migration and push people into cities in different, presumably more prosperous states. A series of positive weather shocks, however, facilitates international migration and migration to cities within the same state. Further, our results indicate that in contrast to other migrants, climate migrants are likely to be from the lower end of the skill distribution and from households strongly dependent on agricultural production. We estimate that approximately 8% of all rural-urban moves between 2005 and 2012 can be attributed to weather. This figure might increase as a consequence of climate change. Thus, a key policy recommendation is to take steps to facilitate integration of less educated migrants into the urban labor market.
Organizing immigration
(2020)
Immigration constitutes a dynamic policy field with – often quite unpredictable – dynamics. This is based on immigration constituting a ‘wicked problem’ meaning that it is characterized by uncertainty, ambiguity and complexity. Due to the dynamics in the policy field, expectations towards public administrations often change. Following neo-institutionalist theory, public administrations depend on meeting the expectations in the organizational field in order to maintain legitimacy as the basis for, e.g., resources and compliance of stakeholders. With the dynamics in the policy field, expectations might change and public administrations consequently need to adapt in order to maintain or repair the then threatened legitimacy. If their organizational legitimacy is threatened by a perception of structures and processes being inadequate for changed expectations, an ‘institutional crisis’ unfolds. However, we know little about ministerial bureaucracies’ structural reactions to such crucial momentums and how this effects the quest for coordination within policy-making. Overall, the dissertation thus links to both policy analysis and public administration research and consists of five publications. It asks: How do structures in ministerial bureaucracies change in the context of institutional crises? And what effect do these changes have on ministerial coordination? The dissertation hereby focusses on the above described dynamic policy field of immigration in Germany in the period from 2005 to 2017 and pursues three objectives: 1) to identify the context and impulse for changes in the structures of ministerial bureaucracies, 2) to describe respective changes with regard to their organizational structures, and 3) to identify their effect on coordination. It hereby compares and contrasts institutional crises by incremental change and shock as well as changes and effects at federal and Länder level which allows a comprehensive answer to both of the research questions. Theoretically, the dissertation follows neo-institutionalist theory with a particular focus on changes in organizational structures, coordination and crisis management. Methodologically, it follows a comparative design. Each article (except for the literature review), focusses on ministerial bureaucracies at one governmental level (federal or Länder) and on an institutional crisis induced by either an incremental process or a shock. Thus, responses and effects can be compared and contrasted across impulses for institutional crises and governmental levels. Overall, the dissertation follows a mixed methods approach with a majority of qualitative single and small-n case studies based on document analysis and semi-structured interviews. Additionally, two articles use quantitative methods as they best suited the respective research question. The rather explorative nature of these two articles however fits to the overall interpretivist approach of the dissertation. Overall, the dissertation’s core argument is: Within the investigation period, varying dynamics and thus impulses for institutional crises took place in the German policy field of immigration. Respectively, expectations by stakeholders on how the politico-administrative system should address the policy problem changed. Ministerial administrations at both the federal and Länder level adapted to these expectations in order to maintain, or regain respectively, organizational legitimacy. The administration hereby referred to well-known recipes of structural changes. Institutional crises do not constitute fields of experimentation. The new structures had an immediate effect on ministerial coordination, with respect to both the horizontal and vertical dimension. Yet, they did not mean a comprehensive change of the system in place. The dissertation thus challenges the idea of the toppling effect of crises and rather shows that adaptability and persistence of public administrations constitute two sides of the same coin.
The increasing application of intersectionality to the psychological study of identity development raises questions regarding how we as researchers construct and operationalize social identity categories, as well as how we best capture and address systems of oppression and privilege within our work. In the continental European context, the use of the intersectionality paradigm raises additional issues, since “race” was officially removed from the vernacular following the atrocities of WWII, yet racialized oppression continues to occur at every level of society. Within psychological research, participants are often divided into those with and without “migration background,” which can reiterate inequitable norms of national belonging while washing over salient lived experiences in relation to generation status, citizenship, religion, gender, and the intersection between these and other social locations. Although discrimination is increasingly examined in identity development research, rarely are the history and impact of colonialism and related socio-historical elements acknowledged. In the current paper, we aim to address these issues by reviewing previous research and discussing theoretical and practical possibilities for the future. In doing so, we delve into the problems of trading in one static social identity category (e.g., “race”) for another (e.g., “migration background/migrant”) without examining the power structures inherent in the creation of these top-down categories, or the lived experiences of those navigating what it means to be marked as a racialized Other. Focusing primarily on contextualized ethno-cultural identity development, we discuss relevant examples from the continental European context, highlighting research gaps, points for improvement, and best practices.
The increasing application of intersectionality to the psychological study of identity development raises questions regarding how we as researchers construct and operationalize social identity categories, as well as how we best capture and address systems of oppression and privilege within our work. In the continental European context, the use of the intersectionality paradigm raises additional issues, since “race” was officially removed from the vernacular following the atrocities of WWII, yet racialized oppression continues to occur at every level of society. Within psychological research, participants are often divided into those with and without “migration background,” which can reiterate inequitable norms of national belonging while washing over salient lived experiences in relation to generation status, citizenship, religion, gender, and the intersection between these and other social locations. Although discrimination is increasingly examined in identity development research, rarely are the history and impact of colonialism and related socio-historical elements acknowledged. In the current paper, we aim to address these issues by reviewing previous research and discussing theoretical and practical possibilities for the future. In doing so, we delve into the problems of trading in one static social identity category (e.g., “race”) for another (e.g., “migration background/migrant”) without examining the power structures inherent in the creation of these top-down categories, or the lived experiences of those navigating what it means to be marked as a racialized Other. Focusing primarily on contextualized ethno-cultural identity development, we discuss relevant examples from the continental European context, highlighting research gaps, points for improvement, and best practices.
The occurrence of refugia beyond the arctic treeline and genetic adaptation therein play a crucial role of largely unknown effect size. While refugia have potential for rapidly colonizing the tundra under global warming, the taxa may be maladapted to the new environmental conditions. Understanding the genetic composition and age of refugia is thus crucial for predicting any migration response.
Here, we genotype 194 larch individuals from an similar to 1.8 km(2)area in northcentral Siberia on the southern Taimyr Peninsula by applying an assay of 16 nuclear microsatellite markers. For estimating the age of clonal individuals, we counted tree rings at sections along branches to establish a lateral growth rate that was then combined with geographic distance.
Findings reveal that the predominant reproduction type is clonal (58.76%) by short distance spreading of ramets. One outlier of clones 1 km apart could have been dispersed by reindeer. In clonal groups and within individuals, we find that somatic mutations accumulate with geographic distance. Clonal groups of two or more individuals are observed. Clonal age estimates regularly suggest individuals as old as 2,200 years, which coincides with a major environmental change that forced a treeline retreat in the region.
We conclude that individuals with clonal growth mode were naturally selected as it lowers the likely risk of extinction under a harsh environment. We discuss this legacy from the past that might now be a maladaptation and hinder expansion under currently strongly increasing temperatures.
Integrated assessment models (IAMs) form a prime tool in informing about climate mitigation strategies. Diagnostic indicators that allow comparison across these models can help describe and explain differences in model projections. This increases transparency and comparability. Earlier, the IAM community has developed an approach to diagnose models (Kriegler (2015 Technol. Forecast. Soc. Change 90 45–61)). Here we build on this, by proposing a selected set of well-defined indicators as a community standard, to systematically and routinely assess IAM behaviour, similar to metrics used for other modeling communities such as climate models. These indicators are the relative abatement index, emission reduction type index, inertia timescale, fossil fuel reduction, transformation index and cost per abatement value. We apply the approach to 17 IAMs, assessing both older as well as their latest versions, as applied in the IPCC 6th Assessment Report. The study shows that the approach can be easily applied and used to indentify key differences between models and model versions. Moreover, we demonstrate that this comparison helps to link model behavior to model characteristics and assumptions. We show that together, the set of six indicators can provide useful indication of the main traits of the model and can roughly indicate the general model behavior. The results also show that there is often a considerable spread across the models. Interestingly, the diagnostic values often change for different model versions, but there does not seem to be a distinct trend.
The large literature that aims to find evidence of climate migration delivers mixed findings. This meta-regression analysis i) summarizes direct links between adverse climatic events and migration, ii) maps patterns of climate migration, and iii) explains the variation in outcomes. Using a set of limited dependent variable models, we meta-analyze thus-far the most comprehensive sample of 3,625 estimates from 116 original studies and produce novel insights on climate migration. We find that extremely high temperatures and drying conditions increase migration. We do not find a significant effect of sudden-onset events. Climate migration is most likely to emerge due to contemporaneous events, to originate in rural areas and to take place in middle-income countries, internally, to cities. The likelihood to become trapped in affected areas is higher for women and in low-income countries, particularly in Africa. We uniquely quantify how pitfalls typical for the broader empirical climate impact literature affect climate migration findings. We also find evidence of different publication biases.
Being perceived as a foreigner regardless of one's generational status, citizenship, or self-identification is called foreigner objectification. This is a form of identity denial and is linked to psychological distress. To test how foreigner objectification could be measured in Europe, we assessed whether the Foreigner Objectification Scale demonstrated reliability and validity with German adolescents. The sample included 806 9th graders from 17 high schools. The results showed that the scale demonstrates good reliability, scalar measurement invariance across gender and citizenship status, and partial scalar measurement invariance across family heritage, generational status, and cultural self-identification. Adolescents who scored higher on the scale also reported greater school behavioral disengagement, lower life satisfaction, and stronger ethnic identity. Our findings suggest that the scale is psychometrically sound and is linked in theoretically consistent ways to adjustment and ethnic identity. We conclude that this scale offers another way to capture subtle discrimination experiences that add to a more comprehensive understanding of discrimination and the related implications in Europe.
Against a background of increasing violence against non-natives, we estimate the effect of hate crime on refugees’ mental health in Germany. For this purpose, we combine two datasets: administrative records on xenophobic crime against refugee shelters by the Federal Criminal Office and the IAB-BAMF-SOEP Survey of Refugees. We apply a regression discontinuity in time design to estimate the effect of interest. Our results indicate that hate crime has a substantial negative effect on several mental health indicators, including the Mental Component Summary score and the Patient Health Questionnaire-4 score. The effects are stronger for refugees with closer geographic proximity to the focal hate crime and refugees with low country-specific human capital. While the estimated effect is only transitory, we argue that negative mental health shocks during the critical period after arrival have important long-term consequences. Keywords: Mental health, hate crime, migration, refugees, human capital.
The field of American Jewish studies has recently trained its focus on the transnational dimensions of its subject, reflecting in more sustained ways than before about the theories and methods of this approach. Yet, much of the insight to be gained from seeing American Jewry as constitutively entangled in many ways with other Jewries has not yet been realized. Transnational American Jewish studies are still in their infancy.
This issue of PaRDeS presents current research on the multiple entanglements of American with Central European, especially German-speaking Jewries in the 19th and 20th centuries. The articles reflect the wide range of topics that can benefit from a transnational understanding of the American Jewish experience as shaped by its foreign entanglements.
In this introductory article to the special issue, we ask what role sexuality plays in the reproduction and contestation of border regimes and think sexuality towards its various entanglements with border control. As borders have been understood as a method for reproducing racialized distinctions, we argue that sexuality is also a method of bordering and illustrate how sexuality works as a key strategy for the capture, containment and regulation of mobility and movement. Taking a transnational approach, we bring together queer scholarship on borders and migration with the rich archive of feminist, Black, Indigenous and critical border perspectives to suggest that these strategies need to be understood in close relation to the (I) intersecting dynamics of colonial histories of racialization, (II) national regimes of reproductive control and (III) the containment of contagion, disease and sexual deviance.
While estimated numbers of past and future climate migrants are alarming, the growing empirical evidence suggests that the association between adverse climate-related events and migration is not universally positive. This dissertation seeks to advance our understanding of when and how climate migration emerges by analyzing heterogeneous climatic influences on migration in low- and middle-income countries. To this end, it draws on established economic theories of migration, datasets from physical and social sciences, causal inference techniques and approaches from systematic literature review. In three of its five chapters, I estimate causal effects of processes of climate change on inequality and migration in India and Sub-Saharan Africa. By employing interaction terms and by analyzing sub-samples of data, I explore how these relationships differ for various segments of the population. In the remaining two chapters, I present two systematic literature reviews. First, I undertake a comprehensive meta-regression analysis of the econometric climate migration literature to summarize general climate migration patterns and explain the conflicting findings. Second, motivated by the broad range of approaches in the field, I examine the literature from a methodological perspective to provide best practice guidelines for studying climate migration empirically. Overall, the evidence from this dissertation shows that climatic influences on human migration are highly heterogeneous. Whether adverse climate-related impacts materialize in migration depends on the socio-economic characteristics of the individual households, such as wealth, level of education, agricultural dependence or access to adaptation technologies and insurance. For instance, I show that while adverse climatic shocks are generally associated with an increase in migration in rural India, they reduce migration in the agricultural context of Sub-Saharan Africa, where the average wealth levels are much lower so that households largely cannot afford the upfront costs of moving. I find that unlike local climatic shocks which primarily enhance internal migration to cities and hence accelerate urbanization, shocks transmitted via agricultural producer prices increase migration to neighboring countries, likely due to the simultaneous decrease in real income in nearby urban areas. These findings advance our current understanding by showing when and how economic agents respond to climatic events, thus providing explicit contexts and mechanisms of climate change effects on migration in the future. The resulting collection of findings can guide policy interventions to avoid or mitigate any present and future welfare losses from climate change-related migration choices.
Postcolonial surveillance
(2022)
Postcolonial Surveillance investigates the long history of the European border regime, focusing on the colonial forerunners of today’s border technologies. The book takes a longue durée perspective to uncover how Europe’s colonial history continues to shape the high-tech political present and has morphed into EU border migration policies, border security, and surveillance apparatuses. It exposes the racial hierarchies and power relations that form these systems and highlights key moments when the past and present interact and collide, such as in panoptic surveillance, biopolitical registers, biometric sorting, and deterrent media infrastructure. The technological genealogies assembled in this book reveal the unacknowledged histories that had to be rejected for the seemingly clean, unbiased, and neutral technologies to emerge as such.
Phone surveys have increasingly become important data collection tools in developing countries, particularly in the context of sudden contact restrictions due to the COVID-19 pandemic. So far, there is limited evidence regarding the potential of the messenger service WhatsApp for remote data collection despite its large global coverage and expanding membership. WhatsApp may offer advantages in terms of reducing panel attrition and cutting survey costs. WhatsApp may offer additional benefits to migration scholars interested in cross-border migration behavior which is notoriously difficult to measure using conventional face-to-face surveys. In this field experiment, we compared the response rates between WhatsApp and interactive voice response (IVR) modes using a sample of 8446 contacts in Senegal and Guinea. At 12%, WhatsApp survey response rates were nearly eight percentage points lower than IVR survey response rates. However, WhatsApp offers higher survey completion rates, substantially lower costs and does not introduce more sample selection bias compared to IVR. We discuss the potential of WhatsApp surveys in low-income contexts and provide practical recommendations for field implementation.
The motility of adherent eukaryotic cells is driven by the dynamics of the actin cytoskeleton. Despite the common force-generating actin machinery, different cell types often show diverse modes of locomotion that differ in their shape dynamics, speed, and persistence of motion. Recently, experiments in Dictyostelium discoideum have revealed that different motility modes can be induced in this model organism, depending on genetic modifications, developmental conditions, and synthetic changes of intracellular signaling. Here, we report experimental evidence that in a mutated D. discoideum cell line with increased Ras activity, switches between two distinct migratory modes, the amoeboid and fan-shaped type of locomotion, can even spontaneously occur within the same cell. We observed and characterized repeated and reversible switchings between the two modes of locomotion, suggesting that they are distinct behavioral traits that coexist within the same cell. We adapted an established phenomenological motility model that combines a reaction-diffusion system for the intracellular dynamics with a dynamic phase field to account for our experimental findings.
Twenty-four scientists met for the annual Auxological conference held at Krobielowice castle, Poland, to discuss the diverse influences of the environment and of social behavior on growth following last year’s focus on growth and public health concerns (Hermanussen et al., 2022b). Growth and final body size exhibit marked plastic responses to ecological conditions. Among the shortest are the pygmoid people of Rampasasa, Flores, Indonesia, who still live under most secluded insular conditions. Genetics and nutrition are usually considered responsible for the poor growth in many parts of this world, but evidence is accumulating on the prominent impact of social embedding on child growth. Secular trends not only in the growth of height, but also in body proportions, accompany the secular changes in the social, economic and political conditions, with major influences on the emotional and educational circumstances under which the children grow up (Bogin, 2021). Aspects of developmental tempo and aspects of sports were discussed, and the impact of migration by the example of women from Bangladesh who grew up in the UK. Child growth was considered in particular from the point of view of strategic adjustments of individual size within the network of its social group. Theoretical considerations on network characteristics were presented and related to the evolutionary conservation of growth regulating hypothalamic neuropeptides that have been shown to link behavior and physical growth in the vertebrate species. New statistical approaches were presented for the evaluation of short term growth measurements that permit monitoring child growth at intervals of a few days and weeks.
In 2022, there were 4.62 billion social media users worldwide. Social media generates a wealth of data which migration scholars have recently started to explore in pursuit of a variety of methodological and thematic research questions. Scholars use social media data to estimate migration stocks, forecast migration flows, or recruit migrants for targeted online surveys. Social media has also been used to understand how migrants get information about their planned journeys and destination countries, how they organize and mobilize online, how migration issues are politicized online, and how migrants integrate culturally into destination countries by sharing common interests. While social media data drives innovative research, it also poses severe challenges regarding data privacy, data protection, and methodological questions relating to external validity. In this chapter, I briefly introduce various strands of migration research using social media data and discuss the advantages, disadvantages, and opportunities.
In 2015, German Chancellor Angela Merkel decided to allow over a million asylum seekers to cross the border into Germany. One key concern was that her decision would signal an open-door policy to aspiring migrants worldwide – thus further increasing migration to Germany and making the country permanently more attractive to irregular and humanitarian migrants. This ‘pull-effect’ hypothesis has been a mainstay of policy discussions ever since. With the continued global rise in forced displacement, not appearing welcoming to migrants has become a guiding principle for the asylum policy of many large receiving countries. In this article, we exploit the unique case study that Merkel's 2015 decision provides for answering the fundamental question of whether welcoming migration policies have sustained effects on migration towards destination countries. We analyze an extensive range of data on migration inflows, migration aspirations and online search interest between 2000 and 2020. The results reject the ‘pull effect’ hypothesis while reaffirming states’ capacity to adapt to changing contexts and regulate migration.